It has become common practice, particularly where a considerable amount of stapling is to be done, to use a stapling gun that is operated by electricity. The electric stapler is particularly useful in professional stapling applications, because considerable force is required to operate a hand stapler and this physical activity, when carried on for a long period of time, is very difficult. The electric stapler not only permits operation over long periods of time without the worker becoming tired, but it also allows an even stronger force available for stapling than is possible with a manually-operated stapler. Nevertheless, there are a number of problems that arise in connection with such electric staplers. One problem that is encountered is that it is not possible to staple directly into the corner between a horizontal surface (for instance) and a vertical surface, as around the edge of a carpeting in a room. Also, there are some applications where it is not desirable to use a strong driving power for driving the staple, while in other applications a very strong force is necessary. Also, since most electric staplers are operated by a solenoid and the power available is alternating current, there is a tendency to bounce which can lead to a destruction of the material being stapled and can also result in irregular placing of the staple, as well as double stapling. These and other difficulties experienced with the prior art devices have been obviated in a novel manner by the present invention.
It is, therefore, an outstanding object of the invention to provide an electric stapler capable of placing a staple close to a vertical surface or the like.
Another object of this invention is the provision of an electric stapler having a capability of selectively driving the stapler at a low force or a high force.
A further object of the present invention is the provision of an electric stapler which is solenoid operated, but in which continuous pressure on the operating switch does not cause repeated operation of the stapler.
It is another object of the invention to provide an electric stapler in which an operating solenoid is energized by a single electrical pulse.
With these and other objects in view, as will be apparent to those skilled in the art, the invention resides in the combination of parts set forth in the specification and covered by the claims appended hereto.